1.) The force of gravity is what we call weight, we define it as:
w=mg
w=5,7kg*9,8m/s²
w=55,86kg (b)
2.) We know that:
power=W/t
power=50J/20s
power=2,5Watts (a)
3.) The work done is equal to the potential energy, so:
Epg=mgh
Epg=63kg*9,8m/s²*7m
Epg=4321J
Now we get the power:
power=W/t
power=4321J/5s
power=864Watts
Now:
1HP=746Watts
=1,16HP (b)
4.) We know that:
F=ma
350N=m*10m/s²
m=350N/10m/s²
m=35kg (b)
5.) d.) Aceleration is tha rate of change in velocity, either positive (increasing) or negative (decreasing)
Option B is the correct answer that show how magnetic field lines should be drawn for the magnets shown in the figure.
<h3>
What is Magnetic Line of Force ?</h3>
The Magnetic Line of Force of a magnet is defined as the line along which a free N - pole would tend to move if placed in the field of a line such that the tangent to it at any point gives the direction of the field at that point.
When the two unlike poles are placed to each other, there will be attraction. And when the two like poles are placed to each other, there will be repulsion. The reason is that the line of force tend to move from the north pole to the south pole.
From the given diagram, the two magnets are of the same south pole. They are of like pole and there will be repulsion between the two magnets.
Therefore, Option B is the correct answer that show how magnetic field lines should be drawn for the magnets shown in the figure.
Learn more about Magnetic Field Lines here: brainly.com/question/17011493
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The circular path that the car is following reveals the presence
of a net force acting on the car.
If there were no net force, pointing toward the center of the circular
path, the car would travel in a straight line.
Complete Question
A lawn mower has a flat, rod-shaped steel blade that rotates about its center. The mass of the blade is 0.65 kg and its length is 0.55 m. You may want to review (Pages 314 - 318) .
Part A What is the rotational energy of the blade at its operating angular speed of 3510 rpm
Part B
If all of the rotational kinetic energy of the blade could be converted to gravitational potential energy, to what height would the blade rise?
Answer:
Part A

Part B

Explanation:
From the question we are told that
The mass of the blade is 
The length is 
The angular speed is 
Generally the moment of inertia of the of this mower is mathematically evaluated as

substituting values


Generally the rotational kinetic energy of the bland is

substituting values


At point where the gravitational potential energy is equal to the rotational kinetic energy we have that

Where P is the gravitational potential energy
substituting values

=> 
Answer:
The work function of the metal is 2.226 eV.
Explanation:
Given;
wavelength of the violet light, λ = 427 nm = 427 x 10⁻⁹ m
maximum kinetic energy, K.E = 0.684 eV
The energy of the incident light is calculated as;

Apply Einstein's photoelectric equation;
E = Ф + K.E
where;
Ф is the work function of the metal
Ф = E - K.E
Ф = 2.91 eV - 0.684 eV
Ф = 2.226 eV.
Therefore, the work function of the metal is 2.226 eV.